It is now possible to monitor from a single surface electrode, volume-conducted events, which appear to represent regional discharges within the brainstem and diencephalon. This project will involve recording and electronically summing such acoustically-evoked responses from severely neurologically impaired, "high-risk", and normal babies. It is aimed at disclosing brainstem and thalamic malfunction in infants at "high-risk" for central nervous system damage and at establishing norms for bioelectric patterns at different ages during the first two years of life.